Sulfur adsorption thermodynamics, metal surfaces

THERMODYNAMICS OF SULFUR ADSORPTION ON METAL SURFACES IN WATER... 

Thermodynamics of Sulfur Adsorption on Metal Surfaces in Water... 

Oudar et al. (112) have studied the influence of sulfur on the hydrogenation of 1,3-butadiene and H2-D2 equilibration over Pt(110). The rates decayed linearly with sulfur coverage, so that each sulfur atom poisons one dissociation site for hydrogen without influencing the activation energies or mechanism. The authors established the first isotherm for sulfur adsorption under actual catalytic reaction conditions. The adsorbed hydrocarbons influenced the equilibrium coverage of sulfur on the Pt surface. The thermodynamics of adsorbed sulfur on several metal single crystal surfaces have been presented by Bernard et al. (114). 

In the first sections of this chapter, the basic effects of adsorbed sulfur on anodic dissolution, on passivation, and on the breakdown of passive films are presented. In a subsequent section the effects of alloyed elements (essentially Cr and Mo) are presented and the way in which they can counteract the detrimental influence of sulfur is emphasized. In the next section, implications of the mechanisms of sulfur-induced corrosion for different areas of practical importance are given, with connections to the related chapters of this book. In the last section of this chapter, the thermodynamic predictions of the conditions of adsorption of sulfur on metal surfaces in water are given. 

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